[eng] Spain is one of the largest seafood markets in Europe and the world. Seafood consumption has traditionally been very high in Spain; in 2005, for instance, around 36.7 kg per capita were consumed (MAPA, several years). However, little attention has been paid to the market and how the different levels of the market chain interact. This paper uses weekly data to analyse the price transmission elasticity of the main twelve seafood products in the Spanish market chain (Ex-vessel, Wholesale and Retail stages). We then investigate the price transmission asymmetry in these market stages. The results have significant implications for demand analysis, market power and margins in the seafood value chain.